The present invention relates to an adjustable vehicle seat, in particular for a truck, having at least one structurally fixed part and at least one adjustable part which is movable relative to the structurally fixed part.
A known vehicle seat of this type has a one-piece seat shell on a seat frame which can be adjusted in its entirety, for example vertically by means of a scissors-type substructure.
It is an object of the present invention to provide an improved adjustable vehicle seat of the type mentioned at the beginning.
In accordance with one aspect of the present invention, an adjustable vehicle seat comprises a seat cushion positioned on both a seat-shell front part and a seat-shell rear part. The seat-shell front part is formed separately from the seat-shell rear part and mounted for moving relative to the seat-shell rear part, so that the seat-shell front part can be adjusted relative to the seat-shell rear part.
As a result of the fact that the seat-shell front part and the seat-shell rear part are formed separately, and the seat-shell front part can be adjusted, in particular independently of the seat-shell rear part, the seat-shell front part can, for example, be adapted individually to the seat user in inclination and/or length of the seat surface. This increases the comfort. The seat surface is defined between the front edge of the seat cushion and the backrest. For a thigh support, it is sufficient if only the seat-shell front part is adjustable and the seat-shell rear part remains fixed, for example as part of a seat frame. It is advantageous for the seat cushion to rest on the seat-shell rear part and be fastened to the seat-shell front part. When the seat-shell front part is adjusted, the seat cushion can then move in a corresponding manner at the same time. In order to enable adjustment in a gap-free manner with the various seat-surface lengths, the seat cushion reaches, for example, a small distance below the backrest. The vehicle seat according to the invention can be used not only in the case of trucks, including coaches, but also in other types of vehicles.
In one preferred embodiment of the present invention, the seat-shell front part can be pivoted relative to the seat-shell rear part in order to adjust its inclination, for example by the seat-shell front part being arranged on a carrier plate which is coupled to the seat frame. The adjustment of the inclination preferably takes place pneumatically via an inflatable cushion which is arranged between the carrier plate and the seat frame. An embodiment of this type can be produced with little outlay on material and in terms of time and is thereby cost-effective. For the pneumatic actuation, the system can be connected to the compressed-air supply of the truck. However, the adjustment of the inclination can also take place hydraulically, electromechanically or manually.
In another preferred embodiment of the present invention, the seat-shell front part can be displaced relative to the seat-shell rear part in order to adjust the seat-surface length, for example by the seat-shell front part being displaceable relative to the carrier plate and being lockable. As a result and for example, a multi-adjustable vehicle seat is provided with few components. For reliable guiding during the seat-surface length adjustment, slideways are provided on the seat-shell front part and/or on the carrier plate. The seat-shell front part is preferably locked by means of a locking bar which is mounted movably on the carrier plate, is movable relative to the seat-shell front part and, for locking purposes, interacts with a toothed segment of the seat-shell front part. This makes reliable locking and easy unlocking possible. For better performance during a crash, the locking bar is advantageously movable transversely to the seat longitudinal direction. The locking bar can likewise be actuated pneumatically by the existing compressed-air supply.